Harden Gopher parsing and recover server goroutinesHEADv1.6.4main

Reject oversized or malformed Gopher selectors as parse errors instead of panicking. Keep search requests bounded, and wrap shared server goroutines with panic logging so one bad connection cannot take down the process.

1 files changed, 66 insertions, 0 deletions

diff --git a/internal/server_test.go b/internal/server_test.go
new file mode 100644
index 0000000..62d8681
--- /dev/null
+++ b/internal/server_test.go
@@ -0,0 +1,66 @@
+package internal_test
+
+import (
+	"context"
+	"fmt"
+	"net"
+	"strings"
+	"sync"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	"tildegit.org/tjp/sliderule/internal"
+)
+
+type captureLogger struct {
+	mu   sync.Mutex
+	logs []string
+}
+
+func (cl *captureLogger) Log(keyvals ...any) error {
+	cl.mu.Lock()
+	defer cl.mu.Unlock()
+
+	for _, val := range keyvals {
+		cl.logs = append(cl.logs, fmt.Sprint(val))
+	}
+	return nil
+}
+
+func (cl *captureLogger) String() string {
+	cl.mu.Lock()
+	defer cl.mu.Unlock()
+
+	return strings.Join(cl.logs, " ")
+}
+
+func TestServerRecoversConnectionPanic(t *testing.T) {
+	var logs captureLogger
+	server, err := internal.NewServer(
+		context.Background(),
+		"localhost",
+		"tcp",
+		"127.0.0.1:0",
+		&logs,
+		func(net.Conn) { panic("boom") },
+	)
+	require.Nil(t, err)
+
+	done := make(chan error, 1)
+	go func() { done <- server.Serve() }()
+
+	conn, err := net.Dial(server.Network(), server.Address())
+	require.Nil(t, err)
+	_ = conn.Close()
+
+	require.Eventually(t, func() bool {
+		return strings.Contains(logs.String(), "panic in server goroutine")
+	}, time.Second, 10*time.Millisecond)
+
+	server.Close()
+	assert.Nil(t, <-done)
+	assert.Contains(t, logs.String(), "boom")
+}